FIGS. 9 and 10 are cross-sectional views of respective prior art bearing devices. Bearing device 10 includes housings 12 and 14 and bearing assembly 16 with rings 18 and 20 and at least one rolling element 22 disposed between and at least partially retained by rings 18 and 20. Spaces 24 and 26 extend from an exterior of device 10 to the bearing assembly. Device 10 can be used in a wet environment in which water can travel through spaces 24 and 26 to assembly 16. Water in assembly 16 is detrimental to the function of assembly 16 and can lead to premature failure of assembly 16.
Bearing 10 in FIG. 9 uses a labyrinth arrangement of spaces 24 and 26 to attempt to limit ingress of water into device 10. For example, spaces 24 and 26 follow serpentine paths so that there is no straight line path from an exterior of device 10 to assembly 16. However, the labyrinth arrangement has limited effectiveness as a means of preventing water ingress. Bearing 10 in FIG. 10 uses seal 28 to attempt to limit ingress of water into device 10. However, seal 28 is only partially successful in limiting water ingress.